The present invention relates generally to fuel tanks for vehicles and, more particularly, to a filler neck assembly for a fuel tank of a vehicle.
It is known to provide a fuel tank such as a metal fuel tank in a vehicle to hold fuel to be used by an engine of the vehicle. In some vehicles, a tank filler neck tube or filler pipe extension extends between a cap and the metal fuel tank. It is also known to provide a solderless filler neck joint for a metal fuel tank. An example of such a solderless filler neck joint is disclosed in U.S. Pat. No. 5,466,016 to Briody et al. In this patent, a solderless fuel tank filler neck joint includes a resilient seal interposed between a flanged opening in the fuel tank and the filler neck tube. The seal is compressed between the filler neck tube and the flange by mechanical deformation of the filler neck tube after it is inserted through the flanged opening. Mechanical deformation pulls the seal into a mating pocket surrounding the flanged opening compressing an annular bead formed on the seal, thereby providing a resilient secure leak tight joint. This process has been extremely reliable and robust relative to potential leaks.
It is known to provide a plastic fuel tank in a vehicle to hold fuel to be used by an engine of the vehicle. Currently in plastic fuel tanks, the tank filler neck tube or fill pipe extension is attached to the plastic fuel tank using a face welding such as hot plate welding, spin welding, etc. Welding of the filler neck tube to the plastic tank requires the use of like materials such as high density polyethylene, which also allows a break in a barrier material such as EVOH inside a tank wall material used to reduce permeation of hydrocarbons, thus making it difficult to meet federal emissions requirements. In addition, the plastic walls of the filler neck tube are not always robust enough when a hose and clamp assembly is used to make a connection to another component of the vehicle. Typically, this type of weld is prone to leaking over time due to stress and fatigue from shear and cantilever loading due to the weld being under a shear force.
Therefore, it is desirable to provide a new filler neck assembly for a plastic fuel tank in a vehicle that is more robust. It is also desirable to provide a filler neck assembly for a plastic fuel tank in a vehicle that eliminates a tank to filler neck tube weld zone. It is further desirable to provide a filler neck assembly for a plastic fuel tank in a vehicle that incorporates a tank filler neck tube.
It is, therefore, one object of the present invention to provide a filler neck assembly for a plastic fuel tank in a vehicle.
It is another object of the present invention to provide a filler neck assembly for a plastic fuel tank in a vehicle that eliminates a tank to filler neck tube weld zone.
To achieve the foregoing objects, the present invention is a filler neck assembly including a plastic fuel tank having a wall with an opening extending therethrough. The filler neck assembly also includes a filler neck tube extending through the opening and having an annular stop flange projecting radially outward from the filler neck tube outside the wall and an annular lock flange projecting radially outward from the filler neck tube formed inside the wall to lock the filler neck tube to the fuel tank. The stop flange and the lock flange provide the sole means for securing the filler neck tube within the opening. The filler neck assembly further includes a seal interposed in the opening between the wall and the filler neck tube and a washer disposed inside the fuel tank between the wall and the lock flange to engage the seal.
One advantage of the present invention is that a new filler neck assembly is provided for a plastic fuel tank in a vehicle. Another advantage of the present invention is that the filler neck assembly eliminates a tank to filler neck tube weld zone. Yet another advantage of the present invention is that the filler neck assembly is simpler and more robust and is not prone to field leakage over time. Still another advantage of the present invention is that the filler neck assembly is lower in cost, has improved quality and does not require high tech equipment for assembly.
Other objects, features, and advantages of the present invention will be readily appreciated, as the same becomes better understood, after reading the subsequent description taken in conjunction with the accompanying drawings.